Origin and metabolism of tetrodotoxin in pufferfishes and newts

假设河豚鱼和蝾螈体内的河豚毒素（TTX）是外源性的，对河豚鱼和蝾螈体内TTX的来源和代谢进行了研究。1.对三陆海岸采集的27种海洋无脊椎动物进行了毒性检测，未发现有毒动物。为了研究河豚毒素在无毒养殖河豚鱼体内的行为，采用静脉插管法对河豚毒素进行了静脉注射。给药后1小时内血中TTX浓度进行性下降，提示TTX可能在某些器官中蓄积。3.无毒河豚鱼腹腔注射TTX后，约有一半蓄积于肝脏。4.对在蝾螈栖息地采集的几种无脊椎动物进行了毒性检测，未发现有毒动物。蝾螈的毒性存在明显的个体差异和局部差异。对不同海拔稻田蝾螈的毒性进行了比较，结果表明海拔对蝾螈的毒性有影响。6.蝾螈的毒性随其生长而变化。成年人是有毒的。幼虫没有那么毒。未成熟蝾螈的毒性尚不清楚。7.在海岸Hemigrapsus sanguineus的体液中发现了高分子量的抗TTX物质。预先给小鼠注射体液对TTX攻击有一定的保护作用。

Supposing that the origin of tetrodotoxin(TTX)in pufferfishes and newts was exogenous, some studies on the origin and metabolism of TTX in these animals were conducted. 1. Toxicity of 27 species of marine invertebrates collected at Sanriku coast was examined, but no toxic animals were found. 2. To investigate the behavior of TTX in non-toxic cultured puffer fish, TTX was administered intravenously via an intravenous cannula. TTX concentration in the blood was progressively decreased in an hour after the administration, suggesting that TTX might be accumulated in certain organs. 3. A half of TTX administered intraperitoneally in non-toxic cultured pufferfish, was accumulated in liver. 4. Toxicity of a few species of invertebrates collected in a marsh inhabited by newts was examined, but no toxic animals were found. 5. There were remarkable individual and local variations of toxicity in newts. Comparison of the toxicity of newts collected from rice fields at different altitude suggested that the altitude has effects on the toxicity of newts. 6. Toxicity of newts changes with their growth. Adults are very toxic. Larvae are not so toxic. Toxicity of immature newts are not known. 7. The shore crab Hemigrapsus sanguineus was found to have anti-TTX substances with a high molecular weight in their body fluid. Preinjection of the body fluid into a mouse was effective to some extent in protecting from TTX challenge.